论文部分内容阅读
本研究旨在探讨模拟失重对大鼠比目鱼肌肌梭神经营养因子3(neurotrophin-3,NT-3)表达的影响。采用大鼠尾部悬吊法建立模拟失重动物模型,按体重配对原则随机将大鼠分为5组,即尾悬吊3d组、7d组、14d组、21d组和正常同步对照组。采用免疫组织化学ABC染色法及酶联免疫吸附实验法(ELISA)检测大鼠比目鱼肌肌梭NT-3的表达。结果显示,大鼠比目鱼肌梭外肌中未见到NT-3表达;正常对照组大鼠比目鱼肌肌梭中,核袋1和核袋2纤维NT-3呈现强阳性表达;模拟失重后,梭内肌纤维的NT-3免疫染色反应进行性降低;NT-3的ELISA定量检测结果显示,正常组、尾悬吊3d组、7d组、14d组和21d组大鼠比目鱼肌NT-3的含量分别为(14.23±1.65)、(14.11±1.53)、(13.09±1.47)、(12.45±1.51)和(9.85±1.52)pg/mg。统计比较显示,尾悬吊14d后,大鼠比目鱼肌NT-3的含量较正常对照组明显减少(P<0.05);而尾悬吊21d后,大鼠比目鱼肌NT-3的表达进一步减少(P<0.01)。以上结果表明,模拟失重可致大鼠比目鱼肌肌梭NT-3的表达明显减少,并且随着模拟失重时间的延长,梭内肌NT-3的表达量进行性减少。提示微重力环境下本体感觉的适应性变化可能与肌梭NT-3的表达减少有关。
The purpose of this study was to investigate the effect of simulated weightlessness on the expression of neurotrophin-3 (NT-3) in the soleus muscle of rats. The animal model of simulated weightlessness was established by rat tail suspension method. The rats were randomly divided into 5 groups according to the principle of body weight matching, namely the tail suspension 3d, 7d, 14d, 21d and normal control group. Immunohistochemical ABC staining and enzyme-linked immunosorbent assay (ELISA) were used to detect the expression of NT-3 in muscle of rat soleus muscle. The results showed that NT-3 expression was not found in the extrafusal muscle of soleus muscle of rats. In the normal control group, the expression of NT-3 in nuclear bag 1 and nuclear bag 2 was strongly positive. In the simulated weightlessness, The NT-3 immunostaining reaction of the intrafusal myofibers was progressively decreased. The results of NT-3 ELISA showed that the content of NT-3 in the rat soleus muscle in the normal group and the tail suspension group was significantly higher than that in the control group (3d, 7d, 14d and 21d) (14.23 ± 1.65), (14.11 ± 1.53), (13.09 ± 1.47), (12.45 ± 1.51) and (9.85 ± 1.52) pg / mg respectively. The statistical comparison showed that the content of NT-3 in rat soleus muscle decreased significantly after 14 days of tail suspension (P <0.05), while the NT-3 expression in rat soleus muscle decreased further after 21 days tail suspension P <0.01). The above results showed that the expression of NT-3 in the soleus muscle decreased significantly under simulated weightlessness, and the expression of NT-3 in the shuttle muscle decreased progressively with the increase of simulated weightlessness. It is suggested that the adaptability of proprioception in microgravity may be related to the decrease of NT-3 expression in muscle.